scholarly journals Epidemiological and clinical insights from SARS-CoV-2 RT-PCR cycle amplification values

Author(s):  
Samuel Alizon ◽  
Christian Selinger ◽  
Mircea T. Sofonea ◽  
Stéphanie Haim-Boukobza ◽  
Jean-Marc Giannoli ◽  
...  

The SARS-CoV-2 pandemic has led to an unprecedented daily use of molecular RT-PCR tests. These tests are interpreted qualitatively for diagnosis, and the relevance of the test result intensity, i.e. the number of amplification cycles (Ct), is debated because of strong potential biases. We analyze a national database of tests performed on more than 2 million individuals between January and November 2020. Although we find Ct values to vary depending on the testing laboratory or the assay used, we detect strong significant trends with patient age, number of days after symptoms onset, or the state of the epidemic (the temporal reproduction number) at the time of the test. These results suggest that Ct values can be used to improve short-term predictions for epidemic surveillance.

Author(s):  
Mahmoud Ahmed Ebada ◽  
Ahmed Wadaa Allah ◽  
Eshak Bahbah ◽  
Ahmed Negida

: Coronavirus Disease (COVID-19) pandemic has affected more than seven million individuals in 213 countries worldwide with a basic reproduction number ranging from 1.5 to 3.5 and an estimated case fatality rate ranging from 2% to 7%. A substantial proportion of COVID-19 patients are asymptomatic; however, symptomatic cases might present with fever, cough, and dyspnoea or severe symptoms up to acute respiratory distress syndrome. Currently, RNA RT-PCR is the screening tool, while bilateral chest CT is the confirmatory clinical diagnostic test. Several drugs have been repurposed to treat COVID-19, including chloroquine or hydroxychloroquine with or without azithromycin, lopinavir/ritonavir combination, remdesivir, favipiravir, tocilizumab, and EIDD-1931. Recently, Remdesivir gained FDA emergency approval based on promising early findings from the interim analysis of 1063 patients. The recently developed serology testing for SARSCoV-2 antibodies opened the door to evaluate the actual burden of the disease and to determine the rate of the population who have been previously infected (or developed immunity). This review article summarizes current data on the COVID-19 pandemic starting from the early outbreak, viral structure and origin, pathogenesis, diagnosis, treatment, discharge criteria, and future research.


Author(s):  
Claudius Härpfer

In recent times we find many plebiscitary acts that seek to democratically legitimize political processes in any direction. They have in common that they interrupt the normal routine of representative democracies to a certain degree and create an extra-daily state of affairs, which entails not only direct but also indirect consequences. The text attempts to systematize some of these mechanisms from a Weberian perspective using Brexit as an example. After a brief overview of Weber’s short-term politically inspired statements on plebiscitary democracy, the text systematizes Weber’s understanding of the state as a bureaucratic apparatus that requires any kind of leader to be controlled. Subsequently, the text discusses the relationship between domination, legality, and rationality in order to finally point out the danger of erosion of truth and legality through the emergence of competing consensus communities in the face of competing conceptions of order.


BMC Medicine ◽  
2021 ◽  
Vol 19 (1) ◽  
Author(s):  
Sahamoddin Khailaie ◽  
Tanmay Mitra ◽  
Arnab Bandyopadhyay ◽  
Marta Schips ◽  
Pietro Mascheroni ◽  
...  

Abstract Background SARS-CoV-2 has induced a worldwide pandemic and subsequent non-pharmaceutical interventions (NPIs) to control the spread of the virus. As in many countries, the SARS-CoV-2 pandemic in Germany has led to a consecutive roll-out of different NPIs. As these NPIs have (largely unknown) adverse effects, targeting them precisely and monitoring their effectiveness are essential. We developed a compartmental infection dynamics model with specific features of SARS-CoV-2 that allows daily estimation of a time-varying reproduction number and published this information openly since the beginning of April 2020. Here, we present the transmission dynamics in Germany over time to understand the effect of NPIs and allow adaptive forecasts of the epidemic progression. Methods We used a data-driven estimation of the evolution of the reproduction number for viral spreading in Germany as well as in all its federal states using our model. Using parameter estimates from literature and, alternatively, with parameters derived from a fit to the initial phase of COVID-19 spread in different regions of Italy, the model was optimized to fit data from the Robert Koch Institute. Results The time-varying reproduction number (Rt) in Germany decreased to <1 in early April 2020, 2–3 weeks after the implementation of NPIs. Partial release of NPIs both nationally and on federal state level correlated with moderate increases in Rt until August 2020. Implications of state-specific Rt on other states and on national level are characterized. Retrospective evaluation of the model shows excellent agreement with the data and usage of inpatient facilities well within the healthcare limit. While short-term predictions may work for a few weeks, long-term projections are complicated by unpredictable structural changes. Conclusions The estimated fraction of immunized population by August 2020 warns of a renewed outbreak upon release of measures. A low detection rate prolongs the delay reaching a low case incidence number upon release, showing the importance of an effective testing-quarantine strategy. We show that real-time monitoring of transmission dynamics is important to evaluate the extent of the outbreak, short-term projections for the burden on the healthcare system, and their response to policy changes.


Significance Many areas of the Caribbean have trade, investment and family connections with communities in Florida. As the state now plays a pivotal role in US electoral politics, crises in the region can take on added political importance for parts of Florida’s electorate. Impacts Forecasts of short-term economic recovery for Florida remain highly uncertain given the continuing impact of the pandemic. Clashing interests across the Caribbean may demand greater coordination of US policy than the government can currently offer. Healthcare and disaster relief capabilities within the state are severely overstretched and could be overwhelmed by a new crisis.


2021 ◽  
pp. 003022282110598
Author(s):  
Hümeyra Aslaner ◽  
Betül Özen ◽  
Zeliha K. Erten ◽  
Mebrure Beyza Gökçek

Urgent measures were taken for those at the age of 65 and over who were at the risk group all over the world due to the COVID-19 pandemic. It is known that many individuals at the age of 65 and over have experienced anxiety due to the uncertainties. This study aimed to determine the anxiety and death anxiety in individuals aged 65 and over who were isolation at home due to being diagnosed with COVID-19 or being in contact during the pandemic process. The study is descriptive and cross-sectional. It was performed with 656 home-quarantined individuals aged between 65–80 years with positive or negative real-time polymerase chain reaction (RT-PCR) test result. A form including questions about the death anxiety and the Coronavirus Anxiety Scale Short Form prepared by the researchers were administered to the individuals by phone call. Of the participants, 49.5% were male. Median COVID-19 anxiety score was 4 (0–18). Anxiety scores of the male and female participants were similar. Participants with negative polymerase chain reaction (PCR) results and those with death anxiety had higher COVID anxiety scores. Death anxiety has increased by 1.661 times in male gender, 1.983 times in RT-PCR positivity and 0.146 times in the presence of symptoms. Individuals with positive COVID-19 test results or those aged 65 and over who had death anxiety and negative COVID-19 test result but who were in home-isolation due to being a contact had higher anxiety score. For this reason, those with death anxiety can be supported in line with their religious beliefs to reduce anxiety. Those with negative PCR test results in quarantine can be adequately informed about the COVID-19.


2021 ◽  
Author(s):  
Oliver Eales ◽  
Andrew Page ◽  
Sonja N. Tang ◽  
Caroline E. Walters ◽  
Haowei Wang ◽  
...  

Genomic surveillance for SARS-CoV-2 lineages informs our understanding of possible future changes in transmissibility and vaccine efficacy. However, small changes in the frequency of one lineage over another are often difficult to interpret because surveillance samples are obtained from a variety of sources. Here, we describe lineage dynamics and phylogenetic relationships using sequences obtained from a random community sample who provided a throat and nose swab for rt-PCR during the first three months of 2021 as part of the REal-time Assessment of Community Transmission-1 (REACT-1) study. Overall, diversity decreased during the first quarter of 2021, with the B.1.1.7 lineage (first identified in Kent) predominant, driven by a 0.3 unit higher reproduction number over the prior wild type. During January, positive samples were more likely B.1.1.7 in younger and middle-aged adults (aged 18 to 54) than in other age groups. Although individuals infected with the B.1.1.7 lineage were no more likely to report one or more classic COVID-19 symptoms compared to those infected with wild type, they were more likely to be antibody positive 6 weeks after infection. Viral load was higher in B.1.1.7 infection as measured by cycle threshold (Ct) values, but did not account for the increased rate of testing positive for antibodies. The presence of infections with non-imported B.1.351 lineage (first identified in South Africa) during January, but not during February or March, suggests initial establishment in the community followed by fade-out. However, this occurred during a period of stringent social distancing and targeted public health interventions and does not immediately imply similar lineages could not become established in the future. Sequence data from representative community surveys such as REACT-1 can augment routine genomic surveillance.


2022 ◽  
Vol 99 (12) ◽  
pp. 7-12
Author(s):  
T. I. Kalenchits ◽  
S. L. Kabak ◽  
S. V. Primak ◽  
N. M. Shirinaliev

The article describes a case of polysegmental destructive viral-bacterial pneumonia complicated with acute pulmonary abscess, pleural empyema, and pneumopleurofibrosis in a 50-year-old female patient infected with the SARS-CoV-2 virus. The first clinical, laboratory and radiological signs of purulent-necrotic inflammation appeared only 20 days after receiving a positive RT-PCR test result with a nasopharyngeal swab. A month later, an emerging abscess in the lower lobe of the right lung was diagnosed. Subsequently, it spontaneously drained into the pleural cavity.Coagulopathy with the formation of microthrombi in small pulmonary vessels is one of the causative factors of lung abscess in patients infected with the SARS-CoV-2 virus.


2020 ◽  
Author(s):  
Nayan Lamba ◽  
Malia McAvoy ◽  
Vasileios K. Kavouridis ◽  
Timothy R. Smith ◽  
Mehdi Touat ◽  
...  

AbstractPURPOSEThe optimal chemotherapy regimen between temozolomide (TMZ) and procarbazine, lomustine, and vincristine (PCV) remains uncertain for newly-diagnosed anaplastic oligodendroglioma (AO). We therefore addressed this question using a national database.METHODSPatients newly-diagnosed with 1p/19q-codeleted W.H.O. grade III AO between 2010-2016 were identified from the National Cancer Database. Predictors of receiving first-line single-agent TMZ vs. multi-agent PCV were assessed by multivariable logistic regression. Overall survival (OS) was estimated by Kaplan-Meier techniques and evaluated by multivariable Cox regression.RESULTS1,360 AO patients were identified: 74.5% (n=1,013) treated with TMZ, 9.6% (n=131) with PCV, and 15.9% (n=216) with no chemotherapy in the first-line setting. In multivariable logistic analysis, PCV utilization increased from 2010 to 2016 (OR=1.38/year, 95%CI: 1.22-1.56, p<0.001) and was less commonly utilized in privately insured patients (OR=0.38 vs. uninsured, 95%CI: 0.15-0.97, p=0.04). In survival analyses (33.1% reached endpoint), there was no difference in unadjusted OS between TMZ (5yr-OS 60.1%, 95%CI: 55.9-64.1) and PCV (5yr-OS 61.1%, 95%CI: 45.6-73.5; p=0.42). There remained no OS difference between TMZ and PCV in the 75.9% (n=1,032) of AO patients that also received radiotherapy (p=0.51), in the Cox regression analysis adjusted by age, extent of resection, and radiotherapy (TMZ vs. PCV HR=1.31, 95%CI: 0.83-2.08, p=0.24), and in subgroup analyses that incorporate KPS or MGMT status.CONCLUSIONSIn a national database of AOs managed in the ‘real-world’ setting, there is no difference in the short-term mortality between first-line TMZ and PCV chemotherapy. These findings provide preliminary data while we await the long-term results from the CODEL trial.


Plant Disease ◽  
2006 ◽  
Vol 90 (11) ◽  
pp. 1461-1461 ◽  
Author(s):  
M. J. Soule ◽  
K. C. Eastwell ◽  
R. A. Naidu

Washington State is the largest producer of juice grapes (Vitis labruscana ‘Concord’ and Vitis labrusca ‘Niagara’) and ranks second in wine grape production in the United States. Grapevine leafroll disease (GLD) is the most wide spread and economically significant virus disease in wine grapes in the state. Previous studies (2) have shown that Grapevine leafroll associated virus-3 (GLRaV-3) is the predominant virus associated with GLD. However, little is known about the incidence and economic impact of GLD on juice and table grapes. Because typical GLD symptoms may not be obvious among these cultivars, the prevalence and economic impact of GLD in Concord and Niagara, the most widely planted cultivars in Washington State, has received little attention from the grape and nursery industries. During the 2005 growing season, 32 samples from three vineyards and one nursery of ‘Concord’ and three samples from one nursery of ‘Niagara’ were collected randomly. Petiole extracts were tested by single-tube reverse transcription-polymerase chain reaction (RT-PCR; 3) with primers LC 1 (5′-CGC TAG GGC TGT GGA AGT ATT-3′) and LC 2 (5′-GTT GTC CCG GGT ACC AGA TAT-3′), specific for the heat shock protein 70 homologue (Hsp70h gene) of GLRaV-3 (GenBank Accession No. AF037268). One ‘Niagara’ nursery sample and eleven ‘Concord’ samples from the three vineyards tested positive for GLRaV-3, producing a single band of the expected size of 546 bp. The ‘Niagara’ and six of the ‘Concord’ RT-PCR products were cloned in pCR2.1 (Invitrogen Corp, Carlsbad, CA) and the sequences (GenBank Accession Nos. DQ780885, DQ780886, DQ780887, DQ780888, DQ780889, DQ780890, and DQ780891) compared with the respective sequence of a New York isolate of GLRaV-3 (GenBank Accession No. AF037268). The analysis revealed that GLRaV-3 isolates from ‘Concord’ and ‘Niagara’ share nucleotide identities of 94 to 98% and amino acid identities and similarities of 97 to 98% with the Hsp70h gene homologue of the New York isolate of GLRaV-3. Additional testing by double-antibody sandwich enzyme-linked immunosorbent assay (DAS-ELISA) using antibodies specific to GLRaV-3 (BIOREBA AG, Reinach, Switzerland) further confirmed these results in the ‘Niagara’ and two of the ‘Concord’ isolates. GLRaV-3 has previously been reported in labrusca cvs. Concord and Niagara in western New York (4) and Canada (1), but to our knowledge, this is the first report of GLRaV-3 in American grapevine species in the Pacific Northwest. Because wine and juice grapes are widely grown in proximity to each other in Washington State and grape mealybug (Pseudococcus maritimus), the putative vector of GLRaV-3, is present in the state vineyards, further studies will focus on the role of American grapevine species in the epidemiology of GLD. References: (1) D. J. MacKenzie et al. Plant Dis. 80:955, 1996. (2) R. R. Martin et al. Plant Dis. 89:763, 2005. (3) A. Rowhani et al. ICGV, Extended Abstracts, 13:148, 2000. (4) W. F. Wilcox et al. Plant Dis. 82:1062, 1998.


2021 ◽  
Author(s):  
Oliver Eales ◽  
Andrew Page ◽  
Leonardo de Oliveira Martins ◽  
Haowei Wang ◽  
Barbara Bodinier ◽  
...  

Since the emergence of SARS-CoV-2, evolutionary pressure has driven large increases in the transmissibility of the virus. However, with increasing levels of immunity through vaccination and natural infection the evolutionary pressure will switch towards immune escape. Here we present phylogenetic relationships and lineage dynamics within England (a country with high levels of immunity), as inferred from a random community sample of individuals who provided a self-administered throat and nose swab for rt-PCR testing as part of the REal-time Assessment of Community Transmission-1 (REACT-1) study. From 9 to 27 September 2021 (round 14) and 19 October to 5 November 2021 (round 15), all lineages sequenced within REACT-1 were Delta or a Delta sub-lineage with 44 unique lineages identified. The proportion of the original Delta variant (B.1.617.2) was found to be increasing between September and November 2021, which may reflect an increasing number of sub-lineages which have yet to be identified. The proportion of B.1.617.2 was greatest in London, which was further identified as a region with an increased level of genetic diversity. The Delta sub-lineage AY.4.2 was found to be robustly increasing in proportion, with a reproduction number 15% (8%, 23%) greater than its parent and most prevalent lineage, AY.4. Both AY.4.2 and AY.4 were found to be geographically clustered in September but this was no longer the case by late October/early November, with only the lineage AY.6 exhibiting clustering towards the South of England. Though no difference in the viral load based on cycle threshold (Ct) values was identified, a lower proportion of those infected with AY.4.2 had symptoms for which testing is usually recommend (loss or change of sense of taste, loss or change of sense of smell, new persistent cough, fever), compared to AY.4 (p = 0.026). The evolutionary rate of SARS-CoV-2, as measured by the mutation rate, was found to be slowing down during the study period, with AY.4.2 further found to have a reduced mutation rate relative to AY.4. As SARS-CoV-2 moves towards endemicity and new variants emerge, genomic data obtained from random community samples can augment routine surveillance data without the potential biases introduced due to higher sampling rates of symptomatic individuals.


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